Conventionally, a dark-current-circuit interruption structure as described in JP H7-169382A, for example, may be provided for an electrical junction box or the like mounted on an automobile, such as a junction box or a fuse box. That is, an automobile electric/electronic system is provided with a circuit (hereinafter referred to as a “dark current circuit”) that constantly consumes power, such as a clock. For the purpose of preventing exhaustion of the battery when operation is suspended for a long period of time, for example, when a vehicle is exported, a dark current fuse, which is a conductive component that conductively connects such a circuit, needs to be removed from the dark current circuit.
Therefore, by using the dark-current-circuit interruption structure as described in JP H7-169382A, a fuse holder serving as a conductive component holder for holding the dark current fuse can be slidably displaced in the insertion/removal direction of a connection terminal of the dark current circuit, and the dark current fuse can be held so as to be switched between a connection position at which the dark current fuse is connected to the dark current circuit and a disconnection position at which the dark current fuse is disconnected from the dark current circuit.
However, for a dark-current-circuit interruption structure having such a conventional configuration, there is a need to switch the position of the conductive component holder relative to the case by causing engaging portions at distal ends of a pair of elastic projecting pieces respectively formed on a pair of opposing side walls of the conductive component holder to move over engaged portions provided on the case, when attaching the conductive component holder to the disconnection position in a case in which the dark current circuit is accommodated, or when switching the conductive component holder from the disconnection position to the connection position. During such a move-over operation, the pair of elastic projecting pieces deform so as to bend outward of the conductive component holder. Accordingly, a region for allowing the pair of elastic projecting pieces to undergo bending deformation needs to be secured on the outer side of the conductive component holder accommodated in the case, thus posing an inherent problem in that it is difficult to reduce the size of the case.
In this respect, it is conceivable to save space by omitting one of the pair of elastic projecting pieces. However, when only one of the side walls of the conductive component holder includes a lock mechanism formed by an engaging portion and an engaged portion, the conductive component holder tends to be inclined relative to the case due to a reaction force of the lock mechanism. As a result, the contact region between the engaging portion and the engaged portion is reduced, and the conductive component holder is likely to come loose from/come out of the case.
JP H7-169382A is an example of related art.